There's a whole range of opinions on that pressure relief valve in the oil pan. Many people just plug it off. Considering you have a pressure relief built into the oil pump, it does provide a redundant method of pressure relief. I personally suspect it has more to do with high RPM pressures.... I would suspect the component most at risk from extremely high oil pressure, such as running at 4,500 RPM+with cold oil would be the o-rings under the VLOM plate. Perhaps the oil filter itself as well. If you do a full delete including the VVT, normally you install a standard pressure oil pump and just plug the thing off. (The VVT actually requires the higher volume oil pump more than the AFM DOD system.) In either case, in the quest to locate oil pressure loss and going for the pickup tube o-ring, this valve is often overlooked.